The present invention relates to a method of epitaxial deposition of an A.sub.III B.sub.V - semiconductor layer on a germanium substrate having a (100) orientation. The method makes possible the manufacture of luminescence diodes on the basis of GaAsP or other ternary semiconductor layers deposited on a Ge substrate of n-type conductivity, followed by a zinc diffusion. For manufacturing devices for optic communications, GaAs epitactic layers are also used.